Heat generation from a battery is directly related to the current it carries. The higher the current, the more heat is generated. In practice, there exists the possibility that an enormous amount of heat may be generated from the battery that is beyond the capability of an external battery thermal management system to reduce sufficiently. The causes of such high heat generation may be from: (1) an extremely high current resulting from an excess load demand or load fault, (2) a battery internal fault, and/or (3) a charge/discharge circuit failure. Additionally, the heat may accumulate rapidly within the battery if the thermal management system fails or cannot quickly transport the heat out, thereby resulting in very high battery temperature.
Traditional battery thermal management systems provide a means of transporting the heat away from the battery by an external active or passive cooling system. For advanced high energy density batteries (e.g., lithium-type batteries), conventional battery thermal management systems are often inadequate in the event of a fault or a continuous abusive condition. Currently, conventional methods do nothing to control the heat generation from within the battery.
As such, there is a need for an improved battery thermal management system that is able to control the heat generation from within the battery such that the temperature of the battery always remains within a safe limit, without compromising the normal load demand.